相关论文: Multiscale distribution of oxygen puddles in 1/8 d…
Oxygen chain fragments are known to appear at the insulator to superconductor transition (SIT) in YBa2Cu3O6+y. However the self organization and the size distribution of oxygen chain fragments is not known. Here we contribute to fill this…
While it is known that the nature and the arrangement of defects in complex oxides have an impact on the material functionalities little is known on control of superconductivity by oxygen interstitial organization in cuprates. Here we…
The organization of dopants in high temperature superconductors provides complex topological geometries that controls superconducting properties. This makes the study of dopants spatial distribution of fundamental importance. The mobile…
It has recently been established that the high temperature (high-Tc) superconducting state coexists with short-range charge-density-wave order and quenched disorder arising from dopants and strain. This complex, multiscale phase separation…
Short-range lattice superstructures have been studied with high-energy x-ray diffuse scattering in underdoped, optimally doped, and overdoped $\rm (Y,Ca)Ba_2 Cu_3 O_{6+x}$. A new four-unit-cell superstructure was observed in compounds with…
We report a temperature-dependent increase below 300 K of diffuse superlattice peaks corresponding to q_0 =(~2/5,0,0) in an under-doped YBa_2Cu_3O_6+x superconductor (x~0.63). These peaks reveal strong c-axis correlations involving the…
The simplest cuprate superconductor La2CuO4+y with mobile oxygen interstitials exhibits a clear phase separation, but only recently a bulk multiscale structural phase separation has been observed by using scanning micro X-ray diffraction.…
High energy x-ray diffraction is used to investigate the bulk oxygen ordering properties of YBa_2Cu_3O_{6+x}. Superstructures of Cu-O chains aligned along the b axis and ordered with periodicity ma, along the a axis have been observed. For…
An unresolved issue concerning cuprate superconductors is whether the distribution of carriers in the CuO(2) plane is uniform or inhomogeneous. Because the carriers comprise a small fraction of the total charge density and may be rapidly…
Neutron scattering measurements have been made on the spin fluctuations in YBa_2Cu_3O_{7-\delta} for different oxygen doping levels. Incommensurability is clearly observed for oxygen concentrations of 6.6 and 6.7 and is suggested for the…
We present local structural evidence supporting the presence of charge inhomogeneities in the CuO2 planes of underdoped La2-xSrxCuO4. High-resolution atomic pair distribution functions have been obtained from neutron powder diffraction data…
Muon spin rotation measurements of the magnetic field distribution in the vortex state of the oxygen deficient high-Tc superconductor YBa{2}Cu{3}O{6.60} reveal a vortex-lattice melting transition at much lower temperature than that in the…
The atomic pair distribution functions (PDF) of four powder samples of YBa2Cu3O6+x (x=0.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modelled using a full-profile fitting approach to…
Understanding the extent and role of inhomogeneity is a pivotal challenge in the physics of cuprate superconductors. While it is known that structural and electronic inhomogeneity is prevalent in the cuprates, it has proven difficult to…
The parent compounds of the copper oxide high-Tc superconductors are unusual insulators. Superconductivity arises when they are properly doped away from stoichiometry1. In Bi2Sr2CaCu2O8+x, superconductivity results from doping with excess…
Measurements of thermal conductivity versus temperature over a broad range of doping in YBa$_2$Cu$_3$O$_{6+x}$ and HgBa$_2$Ca$_{n-1}$Cu$_n$O$_{2n+2+\delta}$ ($n$=1,2,3) suggest that small domains of localized holes develop for hole…
Temperature and composition dependences of high-energy longitudinal optical (LO) phonons in YBa2Cu3O{6+x}, studied by inelastic neutron scattering measurements, provide clear evidence for temperature dependent spatial inhomogeneity of doped…
There are increasing indications that superconductivity competes with other orders in cuprate superconductors, but obtaining direct evidence with bulk-sensitive probes is challenging. We have used resonant soft x-ray scattering to identify…
Electronic functionalities in materials from silicon to transition metal oxides are to a large extent controlled by defects and their relative arrangement. Outstanding examples are the oxides of copper, where defect order is correlated with…
It is well established that the hole density in the prototypical superconductor La$_{2-x}$Sr$_x$CuO$_4$ is very inhomogeneous due to Sr-dopant induced disorder. On the other hand, until recently it is widely believed that the hole…